Press operating mechanism



y 20; 1941. E. N. NECKEL 2,242,539

PRE-SS OPERATING MECHANISM Filed May 9, 1938 2 Sheets-Sheet 1 FIG. "I

lNVEN"l'OR BYEDMUND N. NECKEL ATTORN EYS May 20, 1941; E. N. NECKELPRESS OPERATING MECHANISM Filed May 9, 1938 2 Sheets-Sheet 2 mvsmbk vBYEDMUND N. NECKEL Patented May 20, 1941 uNiTs STTES PRESS OPERATINGMECHANISM Application May 9, 1938, Serial No. 206,713

8 Claims. (Cl. 3825) This invention relates to improvements in pressoperating mechanism and particularly to that type of press in whichcoacting head and bed pressing members move each toward the other.

An object of the present invention is to provide novel operatingmechanism for that type of pressing machine in which a pressing head isfirst moved to a pressing position adjacent a bed, after which the bedis moved into powerful pressure engagement with the head. In such amachine I provide a strut forming member adapted to hold the head inpressing position and operating mechanism for moving the bed intopressure engagement with the head so dependent on the strut formingmember that it is effective to move the bed into pressure engagementonly after the head has reached a safe closed pressing position.

Among the objects of the present invention are the provision of a smallnumber of simple parts effectively arranged to sequentially move apressing head into position adjacent a bed and for thereafter moving thebed into final heavy pressure engagement against the head. The parts areso arranged that one actuating mechanism is operable to produce theseresults sequentially and without depending upon complicated controlapparatus. My invention also providesnove'l connections between a singlepower means and head and bed operating mechanisms so that one stroke ofthe power means actuates both mechanisms sequentially toclose the press.The invention also includes the novel parts and their arrangement asdisclosed in the accompanying specification and drawings and theessential features thereof will be set forth in the claims.

In the drawings, Fig. l is an end elevation of a pressing machineembodying my invention with certain of the parts broken away or shown insection so that the operation will be more clearly understood, thecontrol mechanism of this machine being shown diagrammatically, theposition of the parts with the press open being shown in full lines andcertain of the parts being shown in safe closed position in dot-dashlines; Fig. 2 is a view of a portion of the mechanism of Fig. 1 showingin full lines the safe closed position corresponding to the dot-dashposition of Fig. 1 and in dot-dash lines in Fig. 2 the fully closedposition of the parts; Fig. 3 is a view similar to Fig. 1 showing thepress in fully closed position; Fig. 4 is a rear elevation of the pressin the open position of Fig. 1 with certain of the parts in section;while Fig. 5 is a detail sectional View taken on the line 5-5 of Fig. 4.

In the machine illustrated, a frame l0 supports a pressing bed I l forlimited vertical movement in the frame. In the form here shown the bedis mounted on a bracket or pedestal l2 and is guided in its verticalmovement by pins I3 which pass through suitable bores in the bracket andare spring pressed downwardly so that the bed normally lies in itslowermost position. Extending downwardly below the bed is a pressure pinM by which the raising and lowering of the bed is controlled. Pivotallymounted in the frame for the latter purpose is: a bellcrank l5 having ashort arm l5a operatively engaging the pressure pin I4. and having alonger arm 15b which is connected with the operating mechanism laterdescribed. It will be noted that [the multiplication of this lever is ofthe order of five or six to one and when coupled with the rest of theoperating mechanism supplies a very powerful pressure when the press isclosed.

Pivotally mounted in the frame at l6 inter mediate its ends is a headlever H which carries at its forward end a pressing head 18 adapted tocoact with the bed II in a pressing operation. Either or both of thepressing members may be heated in any suitable manner as desired.Between the point [9 on the rear end of the head lever and the point 20on the frame is connected a toggle 2| which breaks forwardly as shown infull lines in Fig. 1 when the press is open but is movable rearwardlyto' and slightly beyond a straightened position as shown in dot-dashlines so as to form a strut between the rear end of the head lever andthe frame It. When moved to this position the head I8 is in safe closedposition just above the bed as shown in dot-dash lines in Fig. l. Thetoggle 2| holds the head in this position against retrograde movementduring a pressing operation.

Stop means is provided on the frame to hold the toggle 2| in its strutforming position. This is best seen in Figs. 1 and 5 as comprising agenerally U-shaped stop member 22 having a central portion adapted toembrace the toggle 2| and laterally extending wings 22a which are connected to the rear uprights or vertical channels llia of the frame bymeans of pins 23. These pins are threaded into the frame and locked inposition by suitable lock nuts. As best seen in Fig. 5, these pins haveshoulders thereon and the wings 22a are bored out to lit the smallerdiameter of the pins. The larger diameter of the pins form shouldersagainst which the wings engage when the toggle reaches its predeterminedover center position. Coil compression springs 24 are interposed betweenthe wings 22a and the heads of pins 23, These springs are loaded whenthe toggle moves to limiting position against the stop means. Noise orshock absorbing pads 25 may be provided as shown in Fig. 5. Springs 26connected between the rear end of the head lever and the lower rearportion of the frame normally bias the head toward open position andbias the toggle 2| toward broken position.

The means provided for actuating the bellcrank lever in a manner toraisethe bed is dependent upon the movement of toggle 2| to strutforming position before the bed raising mechanism is effective. In theembodiment shown, a second toggle 21 has one end connected to the lowerlink of toggle 2| at 28 and the other end connected to the longer arm|5b of the bellcrank lever at 29. Any suitable means may be provided formoving the toggle 21 in straightening direction, the result of whichwill be to first straighten the toggle 2| and move the head to a safeclosed pressing position until the toggle 2| engages the stop means 22.When this occurs the toggle 21 has a fixed abutment at its left end andfurther straightening of the toggle will rotate the bellcrank lever |5in a counterclockwise direction raising the bed into pressure engagementwith the head.

In the press shown, power means is provided for straightening toggle 21,the mechanism com-- prising a cylinder and piston motor 30 whose pistonrod 30a is connected to the knuckle of toggle 21 at 3|. The cylinder ofmotor 30 is pivotally mounted in the frame at 32. It will be noted thatthe motor has a power stroke substantially in linewith the link 21a. oftog le 21 as it moves from the full line position to the dotdash lineposition of Fig. 1. During this movement the link 21a acts as a.compression member while the link 2'") is a tension member and serves tocontrol the movement of point 3| in an arcuate path about point 29. Stopmeans 33 on the frame suitably cushioned at 33a the movement ofbellcrank lever l5 in a clockwise direction. The members 21a and 21b actin this manner until they reach the full line position of Fig. 2 or thedot-dash line position of Fig. 1, at which point the wing portions 22a.of the stop means have closed the gap and engaged against the largerdiameters of pins 23 so that toggle 2| is in its limited position overcenter. Thus the critical position where centers 28, 3| and 32 are in astraight line has been passed through, this being permitted by reason ofthe fact that when they reached such critical position the toggle 2| hadnot quite reached its limiting position against the stop means 22. Tofurther insure passage through this critical position a spring 34 isprovided connected between the adjacent links of toggles 2| and 21. Astoggle 2| mo-ves toward straightened position this spring 34 iselongated reaching its maximum elongation as the centers 28, 3| and 32pass through dead center. Upon reaching the full line position of Fig.2, the function of links 21a and 21b becomes that of a to gle actingagainst the stationary pivotal point 28 so that continued movement ofpiston rod 30a acts to straighten toggle 21 and moves the bellcranklever I5 is a counterclockwise direction forcing the buck upwardly intoa. powerful pressure engagement with the head. This position of theparts is shown in full lines in Fig. 3.

When the press is closed, springs 24 are loaded for movement in pressopening direction. Springs 26 are also loaded but their tendency is tohold toggle 2| in its over center position. The springs 24 are socalculated that when the: toggle 2| is over center to the rear thesprings 26'- and motor 30 preponderate over springs 24 so' that thepress remains closed, but when the:

motor 30 is deenergized then the springs 24 will overcome the springs 26sufliciently to move toggle 2| back over center in toggle breakingdirection.

The control of motive fluid for motor 30 is by way of conduits 35 and36, valve casing 31, conduit 38, valve casing 39 and conduit 40. Sincethe valves in casings 31 and 39 are alike, one only will be described.In valve casing 31 a normally closed inlet valve 31:; and a normallyopen outlet valve 312) are mounted on a. common stem 310 for actuationby the branch 31d of a manual 3': which is pivotally mounted on asuitable bracket of the frame. The manuals are so located at the frontof the machine as to require a hand of the operator on each of manuals31c and 39e to supply motive fluid to motor 30 until the pressing headreaches safe closed position. Until this position is reached if eithermanual is released the valves return to their normal position thusexhausting motor 30. Means is provided for holding the motor energizedafter the head reaches safe closed position. In the embodiment shown avalve casing 4| having a normally closed inlet valve and a normally openoutlet valve lies in a position to have its valves actuated to fluidsupply position as the toggle 2| passes over center toward the rear.Motive fluid is then supplied through conduits 35, 42, 43, 44 and 45 toservo motors 46 and 41 which are adapted respectively to engage suitablebranches of manuals 31c and 39e so as to hold these manuals in theiroperated positions indicated in dotdash lines in Fig. l and in fulllines in Fig. 3..

The press will thus remain closed as long as desired. To open the presseither or both of the manuals is moved to the dot-dash position of Fig.3 so'as to evacuate motor 30. whereupon springs 24 and 26 will open thepress.

A snubber for the head lever is shown at 48.

The operation of the press is as follows: VTith the parts in the fullline position of Fig. 1, the operator arranges the work on the pressingbed II and then depresses the manuals 31c and 39a thus supplying fluidthrough conduits 35 and 36, valve 31a, conduit 38, valve 39a and conduit40 to themotor 30. The piston rod 30a moves outwardly straightening thetoggle 21 which at the same time through the connection 28 straightensthe toggle 2|. So long as the head, the head lever and the toggle 2| arefree to move, the bed II and its connected parts do not move as they areheavy enough to remain in place during this period of press operation.However when the lower link of toggle 2| engages the stop 22 on theframe, the left end of toggle 21 is held substantially fixed and furtheroperation of motor 30 straightens the toggle 21. This causes movement ofhell crank lever |5 in a counterclockwise direction raising the bed intopressure engagement with the head l8 which at this time is held in thedot-dash position of Fig. 1 or the full line position of Fig. 3 by thetoggle 2| which is now over center toward the rear of the press. Whenthe parts reach this position valve 4| is opened by engagement with thetoggle 2| to supply fiuid to the servo motors 46 and 41 through conduits42, 43,44 and 45. This holds the man-,

uals We and 39e in depressed or actuated position so that the pressremains closed. To open the press either of the manuals is movedupwardly against the action of its holding servo motor which exhauststhe motor 30 and permits springs 24 to kick toggle 2| over centerforwardly, after which springs 26 complete the opening movement of thehead.

What I claim is:

1. In a pressing machine, a frame, coacting head and bed pressingmembers, each movable toward the other for a pressing operation, twotoggles each having an end operatively connected respectively one witheach of said members to move the same in press-closing direction as saidtoggles are straightened, the other end of each toggle having aconnection with the frame, one of said toggles having an operativeconnection with the other toggle so as to straighten the latter bymovement of said one toggle toward straightened position, and one powermeans having operative connections with each of said togg'les andarranged to straighten said toggles sequentially for a press-closingoperation.

2. In a pressing machine, a frame, coacting head and bed pressingmembers, each movable toward the other for a pressing operation, atoggle operatively having one of its ends connected with said bed memberto move the latter in pressclosing direction as said toggle isstraightened, the other end of said toggle being carried by the frame,one power means, means operatively connected with said power means formoving said head member to pressing position adjacent said bed and forholding it there, and an operative connection between said power meansand said toggle effective to move said toggle toward straightenedposition only when said head has been moved to pressing position.

3. In a pressing machine, a frame, coacting head and bed pressingmembers carried by said frame, each movable toward the other for apressing operation, a stop on said frame, means operatively connectedwith said head and movable into strut-forming position against said stopwhen said head is in pressing position adjacent said bed whereby saidmeans holds said head in pressing position, power means having an opera-,tive connection with said bed for moving the latter in press-closingdirection, and said last named operative connection utilizing said firstnamed means as an abutment in such a manner as to exert a pressing forcewhen said first named means reaches position against said stop.

4. In a pressing machine, a frame, a bed mounted for limited verticalmovement in said frame, a bell-crank lever having a short armoperatively connected with said bed for raising it and having a long armextending downwardly in said frame, a head lever pivotally mountedintermediate its ends in said frame, a head mounted on the forward endof said lever and movable by lever oscillation into and out of pressingposition over said bed, a stop on said frame, a memher connected to therear end of said lever and movable against said stop and between; saidframe and head lever in position to form a strut adapted to hold saidhead in pressing position, a toggle connected with said strut-formingmember and said long arm of said bell-crank lever in a manner to movesaid bed upwardly as said toggle is straightened, said toggle beingarranged to move the strut to head-holding position by movement of saidtoggle toward straightened position, and means for moving said member tostrut-forming position and for moving said toggle toward straightenedposition.

5. In a pressing machine, coacting head and bed pressing members, eachmovable toward the other for a pressing operation, two toggles eachhaving an end operatively connected respectively one with each of saidmembers to move the same in press-closing direction as said toggles arestraightened, the other end of said head-moving toggle being connectedwith the frame, said bed moving toggle having its other end connected tosaid head moving toggle so as to straighten the latter by movement ofsaid bed moving toggle toward straightened position, means for stoppingsaid head moving toggle when said head reaches pressing position oversaid bed, and means for moving said bed moving toggle intoggle-straightening direction.

6. In a pressing machine, a frame, a bed mounted for limited verticalmovement in said frame, a bell-crank lever having a short armoperatively connected with said bed for raising it and having a long armextending downwardly in said frame, a head lever pivotally mountedintermediate its ends in said frame, a head mounted on the forward endof said lever and movable by lever oscillation into and out of pressingposition over said bed, a toggle connected between the rear end of saidlever and said frame and breaking forwardly, said toggle being arrangedwhen straightened slightly over center to hold said head in pressingposition over said bed, stop means on said frame for holding said togglein said over center position, a second toggle connected with said firstnamed toggle and said long arm of said bell-crank lever in a manner tomove said bed upwardly as said toggle is straightened, said secondtoggle being arranged to straighten said first toggle by movement ofsaid second toggle toward straightened position, and means for movingsaid second toggle toward straightened position.

7. A pressing machine as in claim 6 in which said stop means is springpressed in toggle-breaking direction when :the press is closed.

8. A pressing machine as in claim 6 in which said last named means is acylinder and piston motor having a power stroke generally in line withthat link of said second toggle which is connected with said first namedtoggle in the position that link occupies when the press is open.

EDMUND N. NECKEL.

